In Flames, along with Dark Tranquillity and At the Gates, pioneered what is now known as melodic death metal.

In 1990, Jesper Strömblad founded the band to write music that combined the melodic guitar style of Iron Maiden with the brutality of death metal, something which Jesper stated he had never heard any band do.

During 1993, In Flames wrote, recorded, and self-produced their debut studio album, Lunar Strain. Since In Flames did not have a vocalist yet, Jesper asked Mikael Stanne (Dark Tranquillity) to provide vocals. In Flames would eventually need another vocalist for the recording of the EP Subterranean, this time Henke Forss would do the job. However, it wasn't until 1995 that current vocalist Anders Fridén (Dark Tranquillity) joined the band.

Björn Gelotte originally joined as a drummer, then switched to guitars a few years (and albums) later.

The Jester Race was recorded and became a classic melodic death metal album. Afterwards, In Flames got to tour with bands such as Samael and Kreator.

The line up changed for the tour of 1997, Niclas Engelin joining as guitarist. However, by the end of that tour in 1998, Niclas left the band. Niclas would rejoin between 2006 and 2007, and then again in 2009 for another tour, this time as Jesper Strömblad's replacement, who couldn't participate in order to get treatment for his alcohol abuse problems.

Strömblad quit In Flames permanently in early 2010, meaning there are no original members left in the band although all the other members at the time had been in the band since at least 1998 (prior to the recording of "Colony").

In November 2015 drummer Daniel Svensson told he would split with the band after finishing touring.